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# File activerecord/lib/active_record/associations/preloader/association.rb, line 70def associated_records_by_ownerowners_map=owners_by_keyowner_keys=owners_map.keys.compactifklass.nil?||owner_keys.empty?records=[]else# Some databases impose a limit on the number of ids in a list (in Oracle it's 1000)# Make several smaller queries if necessary or make one query if the adapter supports itsliced=owner_keys.each_slice(model.connection.in_clause_length||owner_keys.size)records=sliced.map{|slice|records_for(slice)}.flattenend# Each record may have multiple owners, and vice-versarecords_by_owner=Hash[owners.map{|owner|[owner,[]]}]records.eachdo|record|owner_key=record[association_key_name].to_sowners_map[owner_key].eachdo|owner|records_by_owner[owner]<<recordendendrecords_by_ownerend